hw/avr/atmega: Fix wrong initial value of stack pointer

The current implementation initializes the stack pointer of AVR devices
to 0. Although older AVR devices used to be like that, newer ones set
it to RAMEND.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1525
Signed-off-by: Gihun Nam <gihun.nam@outlook.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <PH0P222MB0010877445B594724D40C924DEBDA@PH0P222MB0010.NAMP222.PROD.OUTLOOK.COM>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

diff --git a/hw/avr/atmega.c b/hw/avr/atmega.c
index a34803e64272ba8f1ae1e69dbcb1c3ebc1094b62..31c8992d750bed19e51b31acc3a5469728344e81 100644 (file)
--- a/hw/avr/atmega.c
+++ b/hw/avr/atmega.c
@@ -233,6 +233,10 @@ static void atmega_realize(DeviceState *dev, Error **errp)
 
     /* CPU */
     object_initialize_child(OBJECT(dev), "cpu", &s->cpu, mc->cpu_type);
+
+    object_property_set_uint(OBJECT(&s->cpu), "init-sp",
+                             mc->io_size + mc->sram_size - 1, &error_abort);
+
     qdev_realize(DEVICE(&s->cpu), NULL, &error_abort);
     cpudev = DEVICE(&s->cpu);
 

diff --git a/target/avr/cpu.c b/target/avr/cpu.c
index 44de1e18d1aaf21091e16634daad2f7af194a2af..999c010dedb8f3f946d25bf1fc50a7447ae59b9b 100644 (file)
--- a/target/avr/cpu.c
+++ b/target/avr/cpu.c
@@ -25,6 +25,7 @@
 #include "cpu.h"
 #include "disas/dis-asm.h"
 #include "tcg/debug-assert.h"
+#include "hw/qdev-properties.h"
 
 static void avr_cpu_set_pc(CPUState *cs, vaddr value)
 {
@@ -95,7 +96,7 @@ static void avr_cpu_reset_hold(Object *obj)
     env->rampY = 0;
     env->rampZ = 0;
     env->eind = 0;
-    env->sp = 0;
+    env->sp = cpu->init_sp;
 
     env->skip = 0;
 
@@ -152,6 +153,11 @@ static void avr_cpu_initfn(Object *obj)
                       sizeof(cpu->env.intsrc) * 8);
 }
 
+static Property avr_cpu_properties[] = {
+    DEFINE_PROP_UINT32("init-sp", AVRCPU, init_sp, 0),
+    DEFINE_PROP_END_OF_LIST()
+};
+
 static ObjectClass *avr_cpu_class_by_name(const char *cpu_model)
 {
     ObjectClass *oc;
@@ -228,6 +234,8 @@ static void avr_cpu_class_init(ObjectClass *oc, void *data)
 
     device_class_set_parent_realize(dc, avr_cpu_realizefn, &mcc->parent_realize);
 
+    device_class_set_props(dc, avr_cpu_properties);
+
     resettable_class_set_parent_phases(rc, NULL, avr_cpu_reset_hold, NULL,
                                        &mcc->parent_phases);
 

diff --git a/target/avr/cpu.h b/target/avr/cpu.h
index 8a178627378df7e0a9da1a54581dc09a77722e4b..7960c5c57a8a539d295cd691daf0eeb3d8657a73 100644 (file)
--- a/target/avr/cpu.h
+++ b/target/avr/cpu.h
@@ -145,6 +145,9 @@ struct ArchCPU {
     CPUState parent_obj;
 
     CPUAVRState env;
+
+    /* Initial value of stack pointer */
+    uint32_t init_sp;
 };
 
 /**